An intarsia pattern knitting fabric as shown in FIG. 7 has been conventionally known as a typical knitting fabric knitted by a flat knitting machine. FIG. 7(a) shows an example in which an intarsia pattern knitting fabric 3 with a diamond pattern is knitted in a part of the front body 2 of a sweater 1, and other portions are made of a ground knitting fabric 4. This sweater 1 can be produced seamless as a cylindrical knitting fabric by knitting a back body opposing a front body 2 in parallel to the front body so that the front and back bodies are joined at both ends. In lower portions of the front body 2 and the back body, a rib knitting fabric 5 called a bottom rib is knitted. FIG. 7(b) shows an example in which an intarsia pattern knitting fabric 8 of a vertically striped pattern is knitted in a part of the front body 7 of a sweater 6, and other portions are made of a ground knitting fabric 9.
FIG. 8 shows the basic manner in which a knitting needle is used when knitting a cylindrical knitting fabric including the intarsia pattern knitting fabrics 3 and 8 shown in FIG. 7 with a double bed flat knitting machine having a front needle bed FB and a back needle bed BB. The intarsia pattern knitting fabrics 3 and 8 and the ground knitting fabrics 4 and 9 are knitted using yarns fed from the tips of different yarn carriers. In the front needle bed FB and the back needle bed BB, knitting is performed using knitting needles A, B, C, . . . shown by capital letters for the front bodies 2 and 7 and knitting needles a, b, c, . . . shown by lower-case letters for the back bodies. Therefore, when a yarn as shown by a solid line is used in the portions of the intarsia pattern 3 and 8, a different yarn from that for the intarsia pattern knitting fabrics 3 and 8 is used for the ground knitting fabrics 4 and 9, as shown by a broken line.
FIG. 9 shows a schematic cross-sectional structure of a double bed flat knitting machine 10 that can knit a cylindrical seamless knitting fabric as shown in FIG. 7. In the double bed flat knitting fabric 10, the front needle bed FB and the back needle bed BB are arranged with a tooth mouth 11 interposed therebetween, and include a large number of knitting needles 12 and 13 that can proceed and recede with respect to the tooth mouth 11. The knitting needles 12 and 13 are arranged with an equal pitch in the direction perpendicular to the drawing sheet. A plurality of thread guide rails 14 are suspended so that a plurality of yarn carriers 15 can travel. A carriage 16 can move in the direction perpendicular to the drawing sheet and is provided with a cam mechanism for moving the knitting needles 12 and 13 in the front needle bed FB and the back needle bed BB selectively in the direction parallel to the drawing sheet, and for driving a knitting operation. The carriage 16 couples the front and back needle beds at a bridge portion 17. The bridge portion 17 is provided with a transfer pin 18 so that the pin can emerge and submerge. The transfer pin 18 is engaged with the yarn carrier 15 in the projected state and allows the yarn carrier 15 to travel along the thread guide rail 14, led by the movement of the carriage 16.
When knitting the intarsia pattern knitting fabrics 3 and 8 as shown in FIG. 7, a plurality of thread feeding members such as the yarn carriers 15 are used for feeding yarns as shown in FIG. 8 for the intarsia pattern knitting fabrics 3 and 8 and the ground knitting fabrics 4 and 9. The thread feeding member such as the yarn carrier 15 used for knitting the intarsia pattern portions 3 and 8 is halted near a boundary between the intarsia pattern knitting fabrics 3 and 8 and the ground knitting fabrics 4 and 9 in each knitting course in order to be used again for knitting the intarsia pattern knitting fabrics 3 and 8 in the next course. In other words, different thread feeding members are used for knitting the adjacent knitting fabrics sandwiching the boundary. Therefore, the plurality of yarn carriers 15 are jammed near the boundary between the intarsia pattern knitting fabrics 3 and 8 and the ground knitting fabrics 4 and 9. As a result, the yarn carriers 15 may interfere with each other, and the tip of a knitting needle supplied for the knitting operation may collide against a halted yarn carrier 15. Alternatively, yarn entanglement may occur, that is, a yarn extending from the final stitch of the intarsia pattern knitting fabrics 3 and 8 to a halted yarn carrier is caught by the tip of the knitting needle 12 or 13 when knitting the ground knitting fabrics 4 and 9 adjacent to the intarsia pattern knitting fabrics 3 and 8.
In order to solve such a problem, a thread feeding member for intarsia pattern knitting that can swing and displace a yarn feeding portion of the thread feeding member forward and backward in the traveling direction when knitting the intarsia pattern is considered. For example, the present inventor discloses a structure of a thread guiding apparatus as a thread feeding member that can swing and displace a yarn feeding portion at the tip of the thread feeding member and can be in a state in which the yarn is extending in the direction substantially immediately above from the final stitch when it is halted, and a method for knitting an intarsia pattern, in Japanese Examined Patent Publication JP-B2 61-51061 (1986). When a thread feeding member in which the position of the yarn feeding portion is changed is used, a plurality of intarsia patterns can be inserted when knitting one course with a carriage provided with a plurality of sets of cams for each needle bed. Furthermore, Japanese Examined Patent Publication JP-B2 61-23300 (1986) discloses a related technique that avoids interference between thread guiding apparatuses as thread feeding members by displacing a lower portion having a hole that can guide the yarn in the vertical direction such that the lower portion penetrates the gap between the knitting needles.
FIG. 10(a) shows a case in which when knitting the intarsia pattern 20 divided into three sections 20a, 20b, and 20c, normal carriers 21a, 21b, and 21c in which the yarn feeding portions 26a, 26b and 26c of the thread feeding member are not displaced are used. FIG. 10(b) shows a case in which intarsia carriers 22a, 22b, and 22c in which the yarn feeding portions 27a, 27b and 27c of the thread feeding member are displaced are used. As shown in FIG. 10(a), when knitting the intarsia pattern 20 from the left to the right with the normal carriers 21a, 21b and 21c, if one set of knitting cams is provided with the carriage for each needle bed, knitting is started from the section 20c with the normal carrier 21c on the right side, then knitting is performed in the section 20b with the intermediate normal carrier 21b, and finally knitting is performed in the section 20a with the normal carrier 21a on the left side. The carriage has to make movement including a plurality of reverse movements. This is because the start positions of the normal carriers 21b and 21c are present in the sections 20a and 20b on their left, and when knitting is performed earlier in the sections 20a and 20b on their left, yarns 28 extending from the normal carriers 21b and 21c at the start positions to the first stitch of the sections 20b and 20c may be caught when knitting the sections 20a and 20b. 
In the intarsia carriers 22a, 22b, and 22c shown in FIG. 10(b), in the start positions, yarns 29 extending from the intarsia carriers 22b and 22c present in the sections 20a and 20b on their left to the first stitch in the sections 20b and 20c can extend substantially immediately above by swinging and displacing the yarn feeding portions 27b and 27c. The yarns 29 substantially do not enter the sections 20a and 20b on their left, so that the yarns are not caught even if knitting is performed earlier in the sections 20a and 20b on their left. This is because when knitting in the sections 20a and 20b on their left, even if the positions of the intarsia carriers 22b and 22c are present in the sections 20a and 20b, the yarn feeding portions 27b and 27c are swung and displaced so that the yarns 29 extend substantially immediately above. Therefore, when the intarsia carriers 22a, 22b, and 22c are used, it is possible to knit the intarsia pattern 20 from the left to the right by one movement of the carriage.
In recent years, a technique for producing a seamless product by knitting a garment such as a sweater in the form of a cylinder using a flat knitting machine as shown in FIG. 7 has been developed. The present inventor teaches a method for knitting a fabric employing the front and back needle beds, such as rib knitting, in the form of a cylinder by allocating alternately the knitting needle of each needle bed to the front and back knitting fabric, using a double bed flat knitting machine, in Japanese Examined Patent Publication JP-B2 3-75656 (1991). Furthermore, Japanese Unexamined Patent Publication JP-A 10-1852 (1998) discloses a method for knitting a cylindrical knitting fabric having an intarsia portion.
Japanese Unexamined Patent Publication JP-A 10-1852 discloses two methods for knitting a cylindrical fabric in which an intarsia pattern is designed in the front knitting fabric, not using a thread feeding member dedicated for intarsia provided with a function in that a yarn feeding portion is displaced as shown in FIG. 10(b). However, a thread feeding member in which a yarn feeding portion is fixed as shown in FIG. 10(a) is used. In a first embodiment shown in FIG. 2 of this publication, even if there is no intarsia pattern in the back body in the back needle bed, the back body is knitted in a divided manner in accordance with the boundary portion of the intarsia pattern of the front body, and the thread feeding member is reversed in the course of knitting and return knitting. Therefore, interference between the thread feeding members and yarn entanglement are prevented. In other words, when knitting a course for the ground portion opposing the intarsia pattern, (1) a kick-back of moving the yarn carrier for an intarsia pattern to the inside of the range of the intarsia pattern is performed, and then the ground portion is knitted all the way up to the intarsia pattern, and (2) a kick-back of moving the yarn carriers for an intarsia pattern and a ground portion to outside the range of the intarsia pattern is performed, and then the remaining ground portion is knitted. Furthermore, in a second embodiment shown in FIG. 3 in this publication, it is attempted to prevent interference and yarn entanglement by retracting the thread feeding member used for knitting the intarsia pattern of the front body to the outside of the width of the entire knitting fabric, when knitting the back body.
In the first embodiment disclosed in Japanese Unexamined Patent Publication JP-A 10-1852, return knitting is performed when knitting the back body. As described in paragraph of this publication, stitches are dense in a portion in which the thread feeding member makes a reverse movement in the return knitting, so that the appearance of the knitting fabric may deteriorate. This problem may be solved by decreasing the stitch density in the reverse movement portion, but adjustment is difficult and takes time. Furthermore, since the back body is not knitted without a break but has to be knitted in a divided manner, the productivity is low. In the second embodiment, although there is no need of performing return knitting, it is necessary to feed the yarn to the thread feeding member directly from the above, as described above in paragraph of this publication, so that the manner of feeding the thread is limited and a large number of colors cannot be taken.
When the thread feeding member for intarsia knitting as disclosed in Japanese Examined Patent Publication JP-B2 61-51061 is used, there is no limitation regarding the number of colors or the manner of feeding the thread, and adjustment of the stitch density involved in return knitting is not necessary. However, it is known that the problem of yarn entanglement is not necessarily solved. Even if the yarn feeding portion of the thread feeding member is displaced, the precision of the position in which it stops in the boundary portion of the intarsia pattern is not necessarily sufficient.
FIG. 11 shows a state in which the final stitch of the intarsia pattern is formed with a knitting needle F in the front needle bed FB, for example, and the yarn feeding portion 22 of the intarsia carrier is halted. In the knitting needles F and G, a new loop of the intarsia pattern is formed by a yarn 23, and an old loop 24 is knocked over. If the yarn feeding portion 22 of the intarsia carrier stops at a position in the range A, for example, it can be believed that yarn entanglement does not occur in which a yarn 25 extending from the knitting needle F of the front needle bed FB to the yarn feeding portion 22 is caught by a knitting needle e of the back needle bed BB. This is because there is a difference in height between the yarn feeding portion 22 and the knitting needle F. Therefore, the range A is extended up to a position slightly beyond a point immediately above the knitting needle e. However, it is difficult to halt the yarn feeding portion 22 within the range A because of the halt precision. As shown in FIG. 9, the yarn carrier 15 is a type in which travel led by the carriage 16 along the thread guiding rail 14 suspended above the tooth mouth 11 can be switched between a travel state and a halt state by being engaged with the transfer pin 18 emerging from or submerging into the bridge portion 17 of the carriage 16. When the engagement with the transfer pin 18 is released, the yarn carrier 15 is halted in the middle of the thread guiding rail 14. The characteristics that are difficult to achieve are required, that is, the sliding resistance between the yarn carrier 15 and the thread guiding rail 14 is small to facilitate the movement when being led by the carriage 16, and when not being led by the carriage 16, the movement should not be facilitated. A lubricant is applied to reduce the sliding resistance, and an adsorptive power by a magnet can be utilized in order to increase the braking properties. However, it is difficult to significantly increase the halt precision of the yarn carrier. Therefore, even using the intarsia carriers 22a, 22b and 22c, the yarn feeding portion 22 cannot stay within the range A in which yarn entanglement hardly occurs, and the yarn feeding portion 22 is halted outside the range A, so that yarn entanglement easily occurs.